Closure



I F. E. BAtDWIN.

CLOSURE.

' APPLICATION FILED JAN. 10' L922.

1,423,592. 7 Patented July 25, 1922.

F/a4. F765. F766.

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CLOSURE.

Application filed January 10, 1922.

to provide a closure of glass or other cast or.

moulded substances, which can be produced without excessive loss such asis due to deformation of the moulded surfaces.

The invention will be claimed at the end hereof and will be firstdescribed in connection with the accompanying drawings forming parthereofandin which Figure 1 is a view, principally in section,

illustrating a closure embodying features of theinvention with parts inclosed position- Fig.2 is an elevation of the stopper ele- I mentshowing also the gasket in section. V

Fig. 3 is an elevation of a closure with the parts reversed in respectto Fig. 1.

Fig. 4 is an elevation of a stopper element embodying a modification andshowing the gasket in section.

Fig. 5 is a sectional view of a closure embodying a modification.

Fig. 6 is a detached view of a stopper substantially like that shown inFig. 5, and

Figs. 7 and 8 are an elevation and a section on line 8-8 of a modified]form of stopper element. v

The closure comprises a columnar element 1 having on its curved surfaceone or more lugs 2 located and arranged to engage the thread of thesocket 3, the diameter of the column being less than the diameter of thesocket. As shown the element 1 is provided with a head or seat 4 adaptedto make a tight closure with the socket by means of the gasket 5. Goodresults are attained by the use of an internally tapering neck 6 havingan inside thread which may well be of coarse pitch and of undulatingform in cross-section. The lug or lugs 2, according to the'diameter ofthe socket, are formedand located to engage the threadin the socketloosely. The gasket 5 may well be of easily deformable materialandcircular in cross-v section. On either the mouth or lip of the orifice,as at 7, Fig. 1, or on the under surfaces of the head of the plug as at7*, Fig. 4,

or on both, a seat for the gasket is formed and adapted to prevent thegasket from unduly expanding away from the center of the Specificationof Letters Patent.

Patented July 25, 1922.

Serial No. 528,216.

closure under pressure. In one form of embodiment of my invention thisseat is cut at an angle so as to force the gasket when under pressuretowards the center of the closure.

I donot limit my invention to the above arrangement as it might bereversed by placing the lug in the neck of the closure and the thread onthe plug, Fig. 3, or instead the lugs may assume the form of one or morepartial threads 2, Figs. 5 and 6, as the same results will be obtained.

On account of the deformation in manufacture of the moulded surfaces thehead of the plug frequently contacts at an angle with the seat on thesocket. By using a readily deformable gasket of circular cross-section,

so held in its seat that it cannot unduly expand away from the centerunder pressure, the substance of the gasket is forced away from thepoint of greatest pressure and as it'cannot expand outwardly because ofthe form of the seat, it moves, or might be said to HOW, to the point ofleast compression and occupies more space where the head of the plug isfurthest away from the seat, thereby correcting for the angle of theseat. Thus a tight closure is obtained which would be otherwiseimpossible.

A readily deformable gasket, especially one having a circular crosssection, performs a most important function. It has been found incommercial practice, no matter how carefully and accurately the threadsin an all glass or like closure are moulded, when usingthe hard orsemi-hard flat gasket, always heretofore employed to make the closure,that the friction between the two glass surfaces is, great enough tomake the two glass surfaces sieze or freeze together so that it isimpossible to open the closure. It is for this reason that there is noton the market for sale today a glass bottle having an interior glassscrew stopper which is adapted to make a tight closure. By the use of myeasily deformable gasket circular in cross section, when the stopper islocked in as tightly as possible, the friction produced by the glass toglass movement, prevents the gasket being compressed to its maximumamount, although the pressure is sufficiently great to produce a tightclosure; consequently should the stopper freeze or stick a downwardpressure on the top of the stopper owing to the formation of my thread,will permit the stopper to sink further into the neck and thus break thehindhard gaskets in commercial use.

ing action of the glass to glass, and the stopper can be released withease. The above cannot be accomplished with the semi- F urthermore whenmanufacturing all glass closures of this type commercially in largequantities, the mouth of the container is always more or less deformed.The usual commercial gasket will not conform to these inequalities andthe closure leaks. My construction of the gasket will so conform.

The stopper is cast in a mould which leaves a. ridge or mould seam ormark up the side of the stopper, as shown at 9, and as shown at 9 acrossthe head or seat of the gasket. With the usual semi-hard commercialgasket this leaves a passage along the mould mark 9 and 9 through whichthe liquid may leak and commercially it is too expensive to grind offthis mould mark. With my easily deformable gasket, circular in crosssection and compressed toward the center of the closure, the mould markis easily embedded and surrounded by the round surface of the gasket anda perfectly tight closure without additional expense. This mould mark isa source of trouble in casting a thread on the stopper as it enlargesthe diameter of the stopper at these points and makes a screw threadvery difficult to cast as they enlarge the ortions of the thread wherethey occur an they cannot be commercially removed. I overcome this byreducing the diameter of the element 1 where the mould marks occursufficiently to prevent the highest mould marks interfering with theclosing action.

The tapered thread in the tapered neck Fig. 1, enables the lug or lugsto pass without contact with the first threads at the mouth of thesocket which are those most often deformed in manufacture, and makecontact with those located in the middle of the socket, whichinvestigation has shown to be generally uniform in shape. This cannot bedone with a continuous thread. Furthermore this tapered socket enablesthe plug to seat at once, forming as it does a species of bayonet joint,thus the closure may be effected by a three quarter turn of the pluginstead of requiring three or four turns of the plug as is commonlynecessary with a straight threaded neck and a continuous thread on theplug.

As an article of manufacture this tapered interior thread has a greatadvantage especially when bottles are machine made as it is foundextremely difiicult to withdraw the forming tool when severalrevolutions of the tool have to be made before it can be withdrawn. Withmy construction b proper design of the taper of the neck and the pitchof the thread the tool will release and can be withdrawn afterthree-fourths to one full turn, instead of requiring three or four fullturns as would be necessary did the neck have parallel sides, thusincreasing the speed of manufacture and reducing the cost.

It will be obvious to those skilled in the art that'modifications may bemade in details of construction and arrangement without departing fromthe spirit of the invention which is not limited as to such matters orotherwise than as the prior art and the appended claims may require.

I claim:

1. A closure having in combination a tapering socket of glass, a glassthread on the inside of the socket, a moulded glass plug having meansadapted to loosely the thread, the plu being free for endwise movementprovide by clearance between said means and thread, the wall of the pluwhere the mould seams occur being of s diameter as will provide spacebetween the seams and the thread and to prevent the mould seamsinterfering with the closing action. a readily deformable gasketcircular in cross-section, and a seat for the gasket adapted to compressthe gasket toward the center of the closure, the gasket being capable offurther compression by endwise pressure on the plug after the closurehas been fully completed by screwing and said gasket adapted for theembedment of the mould seam therein.

2. A closure having in combination a glass socket and an entering lassplug having means adapted to looseFy engage the walls of the socket witha rotary motion, the plug being free for endwise movement provided byclearance in said loosely engagin means, the Wall of the plug where themould seams occur being of such diameter as will provide space betweenthe seams and the wall of the socket to prevent the seams interferingwith the closing action, a readily deformable gasket capable of furthercompression after the closure has been fully efi'ected, and a seat forthe gasket formed to prevent undue outward expansion of the gasket underpressure.

3. A closure having in combination a glass socket and an enteringmoulded glass plug having means adapted to engage the wall of the socketwith a rotary closing action, the wall of the plug where the mould seamsoccur being of such diameter as will provide space or clearance andprevent the seams from interfering with the rotary closing action.

4. A screw closure having in combination moulded glass elements formedto loosely engage the one with the inside of the other by a rotaryclosing action, the elements being free for endwise movement rovided byclearance, and a gasket arranged ween the elements and capable offurther compression after the closure by rotation has been fullycompleted.

5. A closure for glass elements of which one enters the other and whichare provided respectively with confronting threads of which one is widerthan the other to provide clearance in combination with a compressiblegasket stressed by turning motion sufficiently to form a closureandcapable of further compression by endwise pressure torelative 1 shiftthe threads in the clearance provided, t us clearing the threads topermit of reverse turning of the parts.

6. A screw closure having in combination 15 a socket member provided atits lip with a seat, a gasket, a plug provided with a head whichcompresses the gasket axially of the plug and onto the lip, there beingthreads of different widths between the plug and socket to affordfurther entering movement of the plug after the closure is completed,the increased pressure on the gasket necessary for such lurther enteringmovement of the plug being relieved by expansion of the gasket above thesocket.

FREDERIO E. BALDWIN.

